Transducer



W. T. HARRls Feb, 1, 1966 TRANSDUCBR 4 SheetSSheet 1 Filed A ri1 15.1960 Feb. 1, 1966 Fi1ed A ri1 15, 1960 w. T. HARRIs RANSDUcER 4SheetsSheet 2 INVENToR Feb.1, 1966 w. T. HARRIS 3,233,213

RANSDUcBR F11ed A ri1 15. 1960 4 Sheets-Sheet by an aco1lsficaHytTanSpaTent rubbef boof 87. The unit in qUeStion haS Tadiating faceS 88and 89, a11 aS de scTibod in gTeatef detail in the aforen1enfionedFatent Z,713,1Z7. In accordance With the pTeSent invention thiS type ofexciter llnit, together vvith its Sheathing boot 87, iS SnLlg1y Teceivedv1,ithin 11oLISing )offion 91 Which haS a fectangulaT cfoSSSectfoncoTfeSponding fo the peripheTal Shape of the excitef unit 79, the unit79 being held in place by f1exible Inefal stfapS Z SecuTed to thehouSing poftion 91 by IneanS of bo1ts 3. TUbu1aT 11otn-1ike hoUSingpoftion 94 is SecIlfed to the houSing poTtion 91 by the bo1tS 93, theTadiating face 88 of the exciter [1Tlit 79 being difocted tovVafd theiIlteTiof of the hofn 4 and Se )arated fhel-effon1 on1y by the strap Z,Which iS acoustica11y tfanSparent at the ffequencieS involved. The hoUS-ing poftionS 1 and 4 are Stiff and acouSticaHy opaq at thoSefTeqnencieS. The horn 9 is open both phySca1- 1y and acoustica1ly af itSend 5, and thefefore iS adapted to be filled vZfth 1he liquidIIlediun1in Which the transducer iS adapted to be in1TnefSed, thaf Hquid11Hing being deS1g nated 9o. The liquid o will thefefoTe be Seen to conStitllte a co1un1n extending essentia11y ffonl the Tadiating face 88 ofthe exciteT unit to the opon hofn end 5. Th1S 1iquid colun1n CorfeSpondSto the liq11id co1UfnnS in the eInbod1Inents of the TeSent inventiondeScTibed above. AS i11 those embodiments, the length of the nqoidco1umn 95 is a n1inof ffaction, and pTefefably noInfnally on the of(1erof one-qnafter, of the wave 1ength in the 1iquid of the vibrationSproduced by the exciter Unft, and the dian1- eter of the open end 95 iSon the SaIne ofdef of Inagni tudo, and Teferably iS SoIneWhat less thanthe length of the 1iqUid co1uInn. L1So aS in the pfeCeding eInbodinentS, the 1ength of the ex cite1 11nit is leSS than the over aH lengthof tho houSing 1, 94.

Since both of the StfapS Z aTe acouStica11y tfanSpaTent at theffeqUencies invo1ved, the exciter unit 7 in the en1 bodiInent of EIG. 11wi11 tend to Topagate vibrationS ffon1 both of itS Tadiating Surfaces 83and 89, to tho Tight and to the left TeSpectively aS vievved in thodravingS. 1adiation to the left, ffon1 the face 89, thiS corfeSpondingto the back of the oveTa11 aSSeInbly, Wi11 be Telafive1y nogligib1ebecauSe of the poof loading at that area, that 1oading SoI1etiIneS being1eSS than 1 (Z ef cn. The preSence of the 1iqt1id co111 nn o at the ighthand end of tho exciter Unif vi11, however, 1oad that end InUCh fnoTehigh1y, and a liquid-11ned hofn 94 Which haS a Q of leSS than 4 mayTeSulf in a loading of aS high aS 810 c pef cII1. 1 `fS a Te Sult thellnit vvi1l have a high Tad1ative oI1t put ffom the mouth of the hoTnand Wi11 exhibit e1cient tranSdncing )o eTties over a felatively bfoadband of ffequencies.

The eInbodiInent diSc1osed in FIG. 12 iS eSSentia11y fhe SaIne aS thafdiSc1oSed in FIG. 11, and feference nuInera1S as uSed in FIG. 11 alealso appHed to FIG. 12 to deSig nate comparab1e structura1 paftS.fIoweveT, the vaTiable position exciter unit of FIG, 12 is specincaHythat diS- c1oSd in Iny Patent 2,822,48Z of FebruaTy 4, 19S8, en fitled,1/afiable-PoSition Transducer, that eXcitef lInit con1pfiSing the statofn1ass aTea 81 and the arInatuTe maSS aroa 8Z having opposed pole faceSS3 and 84 Te Spective1y and connecfed by eSi1ient connecting IneanS 35.Biasing and eneTgiZing WindingS Boo and 8oZ) are pfovided. S iSdeScfibed in n1ofe detai1 in IT1y afofeInentioned Patent Z 82Z,48Z, thefaceS deSignated 88 and 89 afe the Tadiating faceS of the llnit.

1 13 diSc1oSeS in SeIT1i-SchoInatic Inanner the poSi tioning of anexciter llnit genefa1ly deSignafed 7 Wit11in an acouSficany opaqUee1ongafed houSing tube fhat tube having acoustica11y tfanspaTent openendS 99 and 10o. The eXciter unit 97, Which Inay We11 coInpfise thevaTab1e position type of unit Shown in F1GS, 11 and 12, iS located2Vif11 ifS fadiating SurfaceS 88 and 89 Spaced TeSpectively fTon1 theopen ho11Sng ends and 19, thefeby, When the ends of the houSing tube 8becol1Te ooded Wiff1 w o pfoducing 1oding 1iquid columnS at both S1desof the exciter unit 7. By varying the poSitfon of the unit 9 within thetube 3 and by vaTying the length of the tube 98 in accofdance vith thevve11 Tecognized weighting and phaSing pfopefties the anlonnt of Tadiafion pfopagated both to the right and fo the left as viewed in FG- 13Inay be contTOHed and adjusted.

Fof a11 of the inuStfated enbodiInentS it iS pfefeTTed that none of thest1-I1ct]JTe except the exciting 11nit (vibfa tioncaL1Sing n1eanS) andthe 1iquid colL[nn TeSonate ex cept at frequencieS nluch higher thanthose of the pro doced vibTafionS. IIence the 11L1id in the chaInber,including fifSt and Second chambef paftS hen fesent, Vvi11 beacoUSfica11y confained vvithin tho Sufrounding strI1cf11re viff1 a highdegfee of effectiveneSS.

Thefe has now been deScfibed a bas1c and Wholly nove1 Concept of atfanSdncer doSigned fof 11ndefvafer app1ica tionS. In addition to theadvantageS deScribed above concerning sn1a11 Size and 1ow Q, the nove1tTanSducefS do nof confain any Soft pfeSSurefe1eaSe n1atefial and,thefefofe, their o efatng charactefisticS afe not SubStantially alteTedby high an1bienf pfeSSul-e variations. In the en1bodin1entS utiHZng aninSU1ating 1iquid, the eXciter unt 11ouSng iS SIna11 Telative to the1iquid co1Unln, So that the TeSonant freqlTency iS only sightly variedby variationS in an1bient pfeSSUTe. ,1figh e1ficiency and powef handHngcapabHities aTe obtained, coInpaTing favofably vVith, and ofton eceeding, thoSe ChaTacteristics in pfeviouS1y available StTuctufeS.

vVhile the fofegoing description SetS foTfh the pTi11- ciploS of theinvention in connection vVith Specific ap paTafuS it is to bo cleaflyUndefstood that thiS deScriP- tion iS nlade on1y by Way of exanlple andnot as a 1in1ita tion of the Scope of the invention aS Set fofth in thefo1 loWing clain1S.

1, A tranSducef fof UndervafeT acoustic energy pfop agation conlpfisinga houSing having a chan1bef vvith first and Second partS, each of S1dchaInber paTtS being Sub Stantia11y Hed with a 1ic111id, 1neanS in saidTst chaIn ber paft for caUSing the liqoid therein to vibfate at a givonfrequency, n1eanS for o eTatively connecting the 1iq11id in each ofSa1(1 chaInbef paftS fof vibTation tranSIniSSion thefebetvveen, andn1eanS fof tfaI1SInitting the 1iquid vib1a tioI1S in Said ChambeT to theeXtefiof of Said honSing, Said housing Stfucture being eSSentianyacouStica11y opaque to vibfationS at Said given frequency.

2. The tTansdocef of clain1 1, in vvhich Said second chInbef paTt hZLSan acoUStical length Such in coniunction With Said fiT5t chamber paTt aSto forn1 a 1iqllid colUn1n having an effective aconstical lengthTe1ative to said vibTationcauSing nleanS Which iS SubStantia11yone-quaTfeT of the wave length in said chanTbef of vibfationS at saidgiven ffequency.

3. The tfanSducef of c1ain1 2, in which the same liqufd iS in Said fiTstand Second chan1bef partS.

4. The tranSdUcer of C1aim Z, in Which an inS111ating 1iqL1id is in SaidfifSt Chan1bef aTt and liq11id froIn the n1ediUIn SurfoUnding SaidhouSing is in Said Socond chaTnbor part, Safd li(111id in Said f1TSf andSecond chan1bef partS being Se arafed by a parfition inpeTn1eab1e to thef1ow therefhrough of oither of Said liq1Iids, vVhich partition con1priSos said IIleanS fof operative1y conneoting the 1iqUid in each ofSaid chan1beT paTtS.

5. The ffansduceT of c1aiTn Z, in v/hic11 the 1iq11id iT1 Said firSt andSeCond chaInber parts afe SepaTated by a f1L1idin eTIneab1e paft1tionSubStantiany ffeely vibfat able at Said g1Ven frequency, Which )aTtit1oncoInpTiSeS Safd Tneans fof operatiVe1y connecting the 1ic uid iI1 eachof Said chambef paTts.

o. The faSdUcer of C1ailn 5, in Which said vibration ca51ng fnoanScoInpTiSos a VfbTofed driving paft oper2 tiVe1y connoCted fo Saidaftit1on by the 1iquid in Said fffSt chan1be part,

7. The ffanSduCoT of c1aiIn Z, in hich Said 1ifSt ChanT ber aft iSacoUStica11y o )a Uo fo tho extefiof of Said tio1 TanSn1itting Ineanscon1pTiseS a poftion of Said rst chan1ber part and a portion of SaidSecond chan1bef paTt at the end theToof remote ffom Said rSt chambeTpaTt.

11. T he franSducer of clain1 Z in Which Said Second chaInbeT partconlpriSes a hom having an open end Te1T1ote fron1 Said TSt chamber pa.

12. The tfanSduceT of claiIn Z in which Said sec ond chamber patcompTiseS a hofn having an open end Temote ffon1 said St chanbef paTt,and a freely vibTatable diaphTagTn sepaTating Said St and second chamberpaTtS, Said diaphragn1 being ooeratively connected to saidvibrationcaUsfng nleanS and con )rising said neanS foT opeTativelyoonnecting the liquid iIl each of Said chan1 ber pafts.

13. The tTanSducer of c1an 1, iI1 vhich an insulating liquid iS i1 saidfiTSt chan1ber pat and Hquid fToIn the me diuIn surTounding Said houSngiS in Said second chan1beT paTt, Said fiTSt and second cha InbeT partSbeing separated by a partition in1peTneab1e to the ov theTethTough ofeitheI of said liqI1idS, Which paTfition con1pTiseS Said IneanS foTopefatively connecting fhe liqL1id in each of said chaIIIbe1 paTts.

14. The tranSducer of clain1 1, in which said fiISt charnber paTt isacouSticaHy opaque to t11e exteTior of Said housing eXcept via. SaidSecond chambeT part, Said vibTa tiontTanSInitting nleanS being locatedin said Second cham ber part at the end theTeof TeInote froIn Said HTStcham be1 paTt,

15. The tTanSdnceT of clain1 1, in Which Said vibTa tion-TranSn1ittingIneanS cOInpSeS a portion of Said fifSt chanber part and a )oTtio1 ofSaid Second chambef paTt at the end thefeof feInote fmm Said fiTStchambeT paft.

16. The tranSducer of claim 1, in which Said Sec ond ohan1bef partcon1pTiSeS a horn having an open end Temote ffon1 Said rst chan1befpart, and a freely vibTatable diaphragm Separating said fiTSt and Secondchamber pafts, Said diaphragm being operatively connected to saidvibTationcauSing meanS and comprising in said means fO1 o )eTative1yconnectig the liquid in oach of Said chan1 beT parts.

17. A traTLsduceT fof undeTwater acouStic energy rop agation coInpTSinga houSing having a, Cha nber vith TSt and second pafts, leoch of SaidchaTnbef partS being subStantiaHy flled with a liquid, IT1eanS in SaidHTSt chaInber part for cauSing the liquid t he1 ein fo vibTafe at agiven freqllency vVhich is the fesonant frequency of said Ineans, IneanSfor operatively connecting the liquid in each of said chan1beT )aTtS fofvibration tranSIniSSion theTebotween, and IneanS fof tTansn1itting theliquid vibra tions in Said chanlber to the exteTioT of said housing,Said hoosing StrI1ctu1e being eSSentially atco11Stioany o aque tovibrationS at said given ffequency.

1$. The tTanSducer of olaiIn 17, in vvhioh Said second chan1ber part hasan acoustioal length Such in coniuncfion With Sad first chamber paTt aSto folIn a Hqufd column having an effective acoIISticaf length Telativeto Said vi brationcaI1 Sing n1eaJnS vvhich is SubStantiHy one-quarter ofthe vvave length in Said ohaTnbeT of vibrations at said given frequency.

References Ced by fhe Examinet UNITED STATES PATENTS 1 47Z S8 10/ 1923FesSenden et al 3408 1,686,901 10/1928 Culver 3408 1,733 718 10/1929BlondeL 2,40S,2Z6 8/1946 Mason 34010 Z 41L41 11/1945 HayeS 3408 Z,44836S 8/1948 GineSpie. Z ZZ 389 9/19SO Mason 3408 2,52,970 5/19S1 HoTsleyet al.

FREDERICK M. STRADER, CHESTER L IUSTUS, Exo

1. A TRANSDUCER FOR UNDERWEAR ACOUSTIC ENERGY PROPAGATION COMPRISING AHOUSING HAVING A CHAMBER WITH FIRST AND SECOND PARTS, EACH OF SAIDCHAMBER PARTS BEING SUBSTANTIALLY FILLED WITH A LIQUID, MEANS IN SAIDFIRST CHAMBER PART FOR CAUSING THE LIQUID THEREIN TO VIBRATE AT A GIVENFREQUENCY, MEANS FOR OPERATIVELY CONNECTING THE LIQUID IN EACH OF SAIDCHAMBER PARTS FOR VIBRATION TRANSMISSION THEREBETWEEN, AND MEANS FORTRANSMITTING THE LIQUID VIBRA-